Stackhouse Cove

Well the weather couldn't have been better for our survey of Stackhouse Cove last Thursday. The sun was out and there wasn't a breath of wind as we walked through the gorse and bluebells from Prussia cove West till Cudden Point (the eastern boundary of the recommended Mounts bay MCZ). Abby and I were joined by a great and enthusiastic group of volunteers, Jake Meyers, Liz Barker, Rob Wells and Rob Seebold (now of Natuaral England), Jonathan Kersley, Margaret Gardener and Kathry Driscoll. We were lucky to be joined later by Angie Gall who shared her fantastic knowledge with all present, me included!

The view from the point taking in Stackhouse cove and its bizarre criss-crossing gullies, down past Perranuthnoe all the way to St Michaels Mount was breathtaking.

What a day! 

We left Abby on the point with her telescope and sun cream to carry out a sea watch for cetaceans and seals while we walked down the narrow path to the cove.

Stackhouse cove was named after Victorian Naturalist John Stackhouse who was one of the first people to study the reproduction of seaweeds, from his home Acton Castle that overlooks the cove. Although at first sight the shore seemed bare a huge diversity of seaweeds and animals were found near the low water mark. The shore faces south west and is one of the most exposed parts of the MCZ. The terrible battering this coast line experienced this winter may explain the relative lack of seaweeds on all but the lowest shore and the rockpools. On a low shore flat reef Angie pointed out that a huge mass of green gut weed Ulva intestinalis was covering the rock, possibly new successional growth following the winter clear out of seaweeds. Here and there on the smooth slatey rock you would find limpet scars but there were relatively few limpets suggesting these too may have been removed by the force of the sea.

Rob and Mango shore searching

The shore is criss-crossed with spectacular deep gullies which provide their own micro climates. Within one lower shore gully Jake and Rob Seebold found a mass of sponges, hydroids and a group of sea lemons feeding and laying egg masses on this shaded but open rock surface. Prize for the best spot goes to Jake who spotted the legs of a sea spider sticking out from beneath a beadlet anemone. The spider (Nymphon gracilie),  was carrying a mass of eggs below its body. They are predatory animals so I wonder what it was feeding on there? Hydroids or maybe even the anemone!

Sea spider beneath a beadlet anemone - found out of water inside a shady gully

Sea spider - note the egg mass visible beneath the body

In an open area of large flat boulders we found a huge diversity of crustaceans, Montagu's crabs, large velvet swimming crabs, edible crabs, broad clawed porcelain cabs, squat lobsters, plumed bertha sea slugs ,(Bethella plumosa) and even a tiny sea cucumber Pawsonia saxicola.

Female shanny found under a rock 

In cracks facing inshore away from the prevailing swells we found encrusting star ascidians and other colonial sea squirts, being preyed upon by cowries. Beautiful bushy hydroids decorated these gullies and shannies and hairy crabs were hiding in the deepest cracks in the rock.

Male shanny gaurding his eggs in a deep crack in the baked bean seasquirt cave!

Incredible biodiversity beneath a large boulder - Photo taken by Margaret Gardener

Just to summarise how diverse this shore is Margaret sent me a photo she took of a community beneath a large boulder on the lower shore here is what you can see in this photo

1.       Nice colonial ascidian (sea squirt) bright yellow Botryloides leachii,

2.       bright red baked bean sea squirts Dendrodoa grossularia,

3.        Large keel worms Pomatoceros lamarcki,

4.       barnacles,

5.       purple encrusting coralline algae,

6.       black stuff – encrusting brown algae, possibly pterocelis phase of Mastocarpus Stellatus,

7.       Orange encrusting bryozoan Oshurkovia littoralis,

8.       an orange sponge probably Microciona fallax.

9.       Some spirobid worms Spirobis rupestris.

10.   Sea weeds –   Bunny's ears in the bottom left Lomentaria articulata,

11. and a small piece of red seaweed possibly Rhodymenia pseudopalmata

 So total species count from that one photo is  11 but there are probably many more!!  

The highlight of the day was witnessing an overhanging shallow cave where every surface was covered in reddish baked bean sea squirts, sponges and beautiful Actinothoe anemones ( - the fried egg colour variety - a species rarely seen on the shore!)

Angie, Max and the baked bean cave

Baked bean seasquirts  Dendrodoa grossularaia , carpeting the cave

Actinothoe sphyrodeta anemone closed up amongst the Dendrodoa

Actinothoe anemone open 

The diversity of sea weed life is also notable - shallow pools were home to rainbow wrack, tuning fork weed, banded pincer weed and many other notable species and the current scoured gullies were home to species that are used to high levels of water flow such as Alaria esculenta and Laminaria digitata. There were loads of beautiful  tiny new kelp plants growing on the lower shore - most likely Sacchorhiza polyschides, that tasted amazing!

Rainbow wrack  Cystociera tamariskifolia 

Rob Seebold in a seaweed world! 

Desmarets flattened weed - this seaweed is one you shouldn't try eating - contains sulphuric acid! 

Tasty new shoots of juvenile kelps! 

Tiny hermit crab in a grey topshell shell - with a very white smooth and rounded right claw - probably  Anapagurus hyndmanni 

Colonial sea squirt Aplydium proliferum (thanks to Lisa Rennocks for helping with id!)

All agreed that this shore is home to a fantastic diversity of life and one I would like to return to soon!

Honeycomb reefs of St Austell Bay

This winter has been unbelievable - Massive gales and high tides have been battering Cornwall's coast relentlessly since Christmas.  This weekend saw some of the highest tides of the winter and It looked like the Shoresearch Rockpool ramble leaders training day would be a total washout!
Fortunately on Sunday morning we woke to the first sunny day of the year (more or less) and we had a cracking time down on the shore at Spit beach near Par!
It was great to have such a good turnout of lovely people all keen to learn and to gain the skills needed to share their enthusiasm with the public.A total of 22 volunteers took part and they traveled from all over the county, from Polzeath, Fowey, Looe, St Agnes, the Roseland and we also had sevenlocals who are members of the Friends of Par beach. After a couple of slideshows held in Gott hall we walked down (though the floods) to the beach which is right next to Par Docks.

Happy shoresearchers! 

It was really exciting to see how alive and diverse the shore is here so close to the docks - I had heard reports but it was great to see for first hand the beautiful colonies of Honeycomb Worm - Sabellaria alveolata that cover a large area of the mid shore. these worms grow in colonies and they construct their concrete like tubes using sand. The sand they need is very specific and this rare Biodiversity Action Plan species is only found in a handful of locations around the country. The only other place in Cornwall where this species is found is along the coast between Millook and Bude on Cornwall's far north coast.

GPS proof that these rare colonies exist! 

Honeycomb worm colony closeup, Matt Slater

The beach at Spit is made up mainly of quartz sand and gravel, and mica which are waste products from the china clay processing that has been carried out for centuries in this area. It was interesting to see that the tubes were made up mainly of tiny fragments of quartz (plus some shell sand). Perhaps this is the reason why this rare species is found in this one location alone on the south coast of Cornwall?

The shore is very unusual with very few mussels and a large covering of pepper dulse Osmundia pinnatifida over the rocks.

Pepper dulse carpeting rocks, Matt Slater 

Volcano barnacles - Balanus perforatus are very common on this site.

Volcano barnacles Balanus perforatus, Matt Slater

Cystoseira tamariscifolia Rainbow wrack (photo Matt Slater )

 and in the pools we found small rainbow wracks growing as well as the beautiful false eyelash seaweed, sausage weed and young plants of Sargassum muticum.

Snakelocks anemone Photo by Margaret Gardner

There were countless hermit crabs Pagurus bernhardus, daisy anemones, snakelocks, strawberries and beadlet anemones.
We also found a young sea hare - Aplysisa punctata, and a sheep sea slug Aeolida papillosa.

It was great to see large numbers of freshly laid dog whelk eggs! and so many signs of the coming spring on such a beautiful day (amongst such heavy storms!) Including a small spotted sea hare Aplysia punctata.

Sea Hare

Thanks to all who came along and I hope to see you at the next surveys!

Cheers

Matt